Go to a trap that doesn,t have the smells the others have on them. Pull one out that has been sitting out with no lure or smells that would give him an indication it is the same villian
When trapping South of Macon and south of Montgomery in the summer, I have found due to various factors relating to heat and humidity, water temperature, and availability of food the beaver respond differently than other parts of the country. They may come the first time to the castor, but they are more easily spooked or cautious overall with "any" new smell. They may investigate it and get caught the first time, the others seem to treat the catches as time to hold and not move. Due to that nature here in the summer I believe any first night trap set up should be planned with that factor in mind.
Using scent of some kind seems to always inhance the catch the first night. It is the second night or down the road catch that I have found to be a bummer in the deep south.
I have been guilty over the years of taking the easy road the first night's set in the summer and not planning for the next successive nights well enough.